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  • Evolution Of The Witwatersrand Basin: Evidence From The Quartzites.

    Etd thumbnail: Evolution Of The Witwatersrand Basin: Evidence From The Quartzites.
    Type:
    Etd
    Description/Abstract:
    In this dissertation I present a tectonic, geochemical, and thermal history for the Witwatersrand basin, located on the Archean Kaapvaal craton, South Africa. The foreland basin tectonic setting of the Central Rand Group controls both the chemical and the thermal evolution of the basin, and unifies the basin evolution model presented here.
    Creator/Author:
    Ritger, Scott D.
    Submitter:
    UC Libraries
    Date Uploaded:
    03/26/2018
    Date Modified:
    03/26/2018
    Date Created:
    1991
    License:
    All rights reserved

  • Geochemical Characterization Of Black Shale Types In The Midcontinent Pennsylvanian.

    Etd thumbnail: Geochemical Characterization Of Black Shale Types In The Midcontinent Pennsylvanian.
    Type:
    Etd
    Description/Abstract:
    Various geochemical parameters including type and abundance of organic matter (TOC), sulfide-sulfur quantities, fluctuations in bottom-water anoxicity (DOP), metal content differences, and sulfur isotope variations have been assessed in order to characterize Midcontinent Pennsylvanian black shales. Based on these geochemical parameters, the deposits can be grouped into three types: Mecca-type, Heebner-type, and Shanghai-type.
    Creator/Author:
    Schultz, Richard Brian.
    Submitter:
    UC Libraries
    Date Uploaded:
    03/26/2018
    Date Modified:
    03/26/2018
    Date Created:
    1991
    License:
    All rights reserved

  • The Lower Silurian Brassfield Formation: A Condensed Sequence Of Punctuated Deposition?

    Etd thumbnail: The Lower Silurian Brassfield Formation: A Condensed Sequence Of Punctuated Deposition?
    Type:
    Etd
    Description/Abstract:
    The Brassfield Formation is a very thin, highly condensed carbonate unit that encompasses most of the Llandovery (8.5 MMYR) and covers much of the eastern midcontinent. Fifty-six Brassfield outcrops exposed around the flanks of the Cincinnati arch comprise three members, four facies tracts, and seven lithofacies. The three types of condensation recognized in the Brassfield (dynamic bypass, punctuated deposition, and sediment starvation) are related to sea level fluctuations, manifested as a hierarchy of sequence orders, that ultimately controlled the spatial and temporal distribution of facies.
    Creator/Author:
    Norrish, Winston Alfred.
    Submitter:
    UC Libraries
    Date Uploaded:
    03/26/2018
    Date Modified:
    03/26/2018
    Date Created:
    1991
    License:
    All rights reserved

  • The Hydraulic Fracturing Of Soil.

    Etd thumbnail: The Hydraulic Fracturing Of Soil.
    Type:
    Etd
    Description/Abstract:
    Little is known about the hydraulic fracturing of soil, although the technique holds potential for several environmental engineering applications. The dissertation research consists of laboratory experiments, where hydraulic fractures were created by injecting dyed glycerin into colluvium contained in a triaxial pressure cell, and a field test, where hydraulic fractures were created by injecting guar gum gel at shallow depths in glacial drift. The laboratory tests showed that hydraulic fractures are readily created in clayey-silt colluvium. Furthermore, hydraulic fractures created in soil with positive pore pressure were filled with two fluids: one injected to create the fracture, and pore fluid that infiltrates into the fracture tip. The length of the infiltrated tip increases with increasing fracture length.
    Creator/Author:
    Murdoch, Lawrence Corlies, Iii.
    Submitter:
    UC Libraries
    Date Uploaded:
    03/26/2018
    Date Modified:
    03/26/2018
    Date Created:
    1991
    License:
    All rights reserved